One application of magnetic recording is hard disk drives. It is well known in the hard disk drive industry that a head over-coat (HOC) film is deposited on the ABS of a read-write head (e.g., such as the read-write head of a slider) to provide corrosion and wear resistance to the device. The traditional HOC film has a bi-layer structure, where a seed layer is deposited onto the device substrate first, followed by carbon film deposition. The seed layer deposition may be achieved by ion beam or magnetron sputtering deposition technologies. In both cases, seed layer material is sputtered off of a target by energetic Ar ions onto the substrate where the sliders are populated. The carbon film deposition employs filtered cathodic arc (FCA) technology.
Over the years, the seed layer material has evolved from pure Si to various mixtures of materials including Si. This is motivated by improved corrosion and wear resistance that derives from a harder and denser seed layer, which enables a reduction in the overall thickness of the HOC film. A thinner HOC film translates to narrower head to media spacing (HMS), and enhances electro-magnetic performance of the read-write head. However, the space for performance improvement from the traditional seed layer is limited by strength of selected seed layer bonds and their packing densities.